Expansible well-drill.



PATBNTED NOV. 1, 1904.

J. R. GRIFFITH.

EXPANSIBLE WELL DRILL.

APPLICATION FILED MAR. 7, 1904.

N0 MODEL.

UNTTnn STATES Patented November 1, 1904.

PATENT Trice.

EXPANSIBLE WELL-DRILL.

SPECIFICATION formingpart of Letters Patent No. 774,071, dated November 1, 1904.

Application filed March 7, 1904:. Serial No. 197,026. (No model.)

To all whom, it may concern:

Be it, known that I, JOHN R. GRIFFITH, a citizen of the United States, residing at Zion City, in the county of Lake and State of Illinois, have invented a new and useful Expansible ell-Drill, of which the following is a specification.

Thisinvention relates to the art of Welldrilling, and has for its object to provide an,

improved drilling-tool particularly adapted for use in deepening drilled wells which are provided with the usual casings.

My invention contemplates anovel arrangement of drilling-bits whereby the latter may be drawn together or contracted for convenience in lowering the tool through the wellcasing and are also capable of being separated or expanded to a diameter greater than that of the casing after the tool has been lowcred below the bottom thereof, thereby to drill a hole of greater diameter than the casing to permit ofthe latter being sunk therein to the desired depth. signed to provide for locking the bits in their operative positions, so as to prevent accidental displacement thereof during the drilling operation, and also to provide for conveniently releasing and contracting the bits within the compass of the tool for convenience in withdrawing the latter from the well without removing the casing.

WVith these and other objects in view the present invention consists in the combination and arrangement of parts, as will be hereinaftor more fully described, shown in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that changes in the form, proportion, size, and minor details may be made within the scope of the claims without departing from the spirit or sacrificing any of the advantages of the invention.

In the drawings, Figure 1 is a side elevation of a portion of a well-drilling tool embodying the features of the present invention- Fig. 2 is a sectional view taken on the line 2 2 of Fig. 1. Fig. 3 is adetail view, partly broken, showing the drill-bits in their lowermost position. Fig. 4 is an inverted plan View of the drillstock with the bits removed. Fig. 5 is a simi- It is furthermore de-' lar view with the bits in place. Fig. 6 is a detail view of one of the bits.

Like characters of reference, designate corresponding parts in each and every figure of the drawings.

In explanation of the present device, reference being had to the accompanying drawings, the numeral 1 designates an ordinary drillstock, which is changed but slightly in carrying out the present invention. This change consists in forming longitudinal sockets or recesses 2 and 3 in the lower portion of the stock, each socket intersecting the bottom of the stock and the outer side thereof. As clearly indicated in Figs. 3 and 1 of the drawings, it will be seen that the sockets intersect opposite sides of the stock, with their adjacent sides-in diametric aliner'nent, whereby it will be understood that the sockets are located in opposite quartersections of the stock. The back of each socket (indicated at 4) is inclined inwardly and downwardly, whereby the socket diminishes in size upwardly and the back forms a beveled or wedge face for a purpose as will hereinafter appear. Formed in the back of each socket and near the upper end thereof there is a recess or seat 5.

Fitted in each of the longitudinal sockets of the drill-stock is one of the present forms of bits 6. The front and rear or inner and outer faces 8 and 9, respectively, of the bit are converged upwardly at the same angle as the inclined back of the socket in the drill-stock, whereby the bit is tapered longitudinally and is wider at the bottom than at the top. The bottom of the jaw or blade is beveled downwardly in opposite directions from the upright sides of the bit to provide a central cutting edge lO. Piercing the upper portion of the bit from front to rear thereof is a perforation or passage 12, and a comparatively short longitudinal groove 13 leads downwardly from the outer end of this passage, thereby forming an inverted substantially L-shaped opening. l/Vithin this L-shaped opening is a substantially L-shaped latch or dog 14, the horizontal arm of which works in the passage or perforation 12, with its inner end projected at the inner face of the bit, and is yieldably held in this position by means of a spring 15, in-

terposed between the lower portion of the dog and the back of the groove. Upon the inner face of the upright member of the dog is a knuckle or projection 16, which bears against the back of the groove and constitutes a bearing-or fulcrum upon which the dog is designed to rock. The outer edge of the dog is inclined downwardly and outwardly, as at 17, so as to enlarge the dog sufiiciently to project externally at the front of the bit and constitute a beveled or cam-shaped trip for use as will be hereinafter described.

hen the bits are in the respective sockets, they are capable of sliding up and down therein, and in view of the inclined backs of the sockets the bits will be forced apart or separated by said. backs when the bits are drawn upwardly, and, reversely, the bits will be drawn together when they are moved downwardly. To insure a positive lateral working of the bits, it is designed to have a positive and slidable tongue and groove connection between each bit and the drill-stock, as best shown in Fig. 3 of the drawings, wherein 18 indicates the tongue or projection, which slides in a groove or way 19, the latter being sub- 1 stantially parallel with the back of the bitsocket, so as to compel the bit to work laterally when it is raised and lowered. Thegroove or way is of course closed at its lower end to limit the downward movement of the pro- I jection, and thereby constitute a stop the downward movement of the bit.

In employing the present tool the well-casto limit ing is first elevated sufliciently to permit of the working of the tool below the bottom of the casing, after which the tool is lowered through the casing, the dogs or latches 14 having been previously disengaged from the seats or recesses 5 in the upper ends of the bit-sockets, whereby the bits are permitted to drop down to their lower limits and are thereby drawn together, so as to occupy transversely less space than the diameter of the tool, to permit of the latter being conveniently lowered through the well-casing. hen the lower ends of the bits strike the bottom of the well, they are stopped thereby; but the drill-stock is still further lowered, so as to slide down over the bits, whereby the latter are drawn apart through the medium of the tongue-andgroove connections between the bits and the stock until the dogs or latches snap into the respective seats 5, whereby the bits are firmly locked in position for operation.

To withdraw the tool from the well, it is merely necessary to haul up the tool without any previous preparation and without removing the well-casing. This is made possible by reason of the strips or cam portions 17 of the latches or dogs projecting externally of the drill-stock, so as to contact with the bottom edge of the well-casing, and thereby rock the dogs to withdraw the same from engagement with the stock and permit the bits to gravitate to their lowermost positions, where they will be drawn together, as hereinbefore explained, and the tool may be conveniently drawn through the casing.

An important feature of the present invention resides in having the locking device 14 l carried by the bit, whereby it lies within the I path of the stock when being lowered and raised through a well-casing, and therefore it y is impossible for the locking device to engage 5 with the well-casing and become wedged or J caught thereon and interfere with the convenient lowering and raising of the tool.

Having thus described the invention, what is claimed, and desired to be secured by Letters Patent, is

1. A well-drilling tool comprising a socketed stock, a bit slidable within the socket of the stock, and means carried by the bit to detachably interlock the latter with the stock and having a part projected externally of the stock to forma trip for engagement with a wellcasing to release the bit from the stock when in its operative position, and located within the path of the stock in the inoperative positionof the bit to permit lowering and raising l of the tool through a well-casing without frici tional engagement between the trip and the j casing. l 2. A well-drilling tool comprising a stock l having a socket intersecting the bottom and one side of the stock, a bit slidable within the socket and capable of working through the lower end thereof, and means carried by the l bit to detachably lock the latter with the stock and having a portion projected outwardly through the open side of the socket to constitute a trip for engagement with a well-casing to release the bit from the stock when in its operative position, and located within the path of the stock in the inoperative position of the bit to permit lowering and raising of the tool through a well-casing without frictional engagement between the trip and the casing.

3. A well-drilling tool comprising a socketed stock, a bit slidable within the socket of the stock, and a spring-actuated latch carried by the bit and having a detachable interlocking engagement with the stock, a portion of the latch being projected externally of the stock and forming a trip disposed for engagement the stock when in its operative position, and located within the path of the stock in the inoperative position of the bit to permit lowering and raising of the tool through a well-casing without frictional engagement between the trip and the casing. I t. Awell-drilling tool comprisinga socketl ed stock, a bit slidable within the socket of the stock, and an intermediately-pivoted springactuated latch carried by the bit, one end of the latch having a detachable interlocking engagement with the stock, and the opposite end l of the latch being projected externally of the with a well-casing to disengage the latch from stock to form a trip disposed for engagement with a well-casing to release the latch from the stock when in its operative position, and located within the path of the stock in the inoperative position of the bit to permit lowering and raising of the tool through a wellcasing without frictional engagement between the trip and the casing.

5. A well-drilling tool comprising a socketed stock, a bit slidable within the socket of the stock, and a substantially L-shaped latch carried by and intermediately pivoted upon the bit, the inner end of the latch having a detachable interlocking engagement with the stock, and the outer end being projected externally of the stock to form a trip disposed for engagement with a well-casing to release the latch from the stock when in its operative position, and located Within the path of the stock in the inoperative position of the bit to permit lowering and raising of the tool through a well-casing without frictional engagement between the trip and the casing.

6. A well-drilling tool comprising a socketed stock, a bit slidable within the socket of the stock, and a rocking latch piercing the bit and carried thereby, one end of the latch having a detachable interlocking engagement with the stock, and its opposite end being projected externally of the stock to form a trip disposed for engagement by a well-casing to release the latch from the stock when in its operative position, and located Within the path of the stock in the inoperative position of the bit to permit lowering and raising of the tool through a well-casing without frictional engagement between the trip and the casing.

'7. A well-drilling tool comprising a socketed stock, a bit slidable within the socket of the stock, and provided with a passage piercing the bit from front to rear and also having a groove formed in the outer face of the bit and in communication with the passage, and a substantially L-shaped spring-actuated latch having one member working in the passage with its inner end in detachable interlocked engagement with the stock, and the other member of the latch having a portion projected externally of the stock to form a trip disposed for engagement with a Well-casing to disengage the latch from the stock When in its operative position, and located within the path of the stock in the inoperative position of the bit topermit lowering and raising of the tool through a Well-casing without frictional engagement between the trip and the casing.

8. A well-drilling tool comprising a stock having a socket intersecting the bottom and one side thereof, an endWise-slidable and laterally-movable bit working in the socket, a projection and groove-guiding connection between the bit and the stock and disposed at an inclination to the longitudinal axis of the 7 stock to Work the bit laterally during its endwise movement, and a' latch carried by the bit with one end having a detachable interlocked engagement with the stock and its opposite end projected outwardly through the open side of the socket to form a trip disposed for engagement with a well-casing to release the latch from the stock when in its operative position, and located within the path of the stock in the inoperative position of the bit to permit lowering and raising of the tool through a well-casing Without frictional engagement between the trip and the casing.

In testimony that I claim the foregoing as my own I have hereto aflixed my signature in the presence of two Witnesses.

JOHN R. GRIFFITH.

Witnesses:

H. W. SOLLENBERGER, R. L. MADDEN. 

